Warner Bros. Interactive has announced a first person shooter set in the Batman’s universe at their pre-E3 event, from F.E.A.R. dev Monolith Productions. The game is entitled Gotham City Imposters, and will allow you to control a character in the fashion of Batman or Joker. The “good guy” concept seams to be more or less based off of the idea presented in the Dark Knight where wanna be heroes dress themselves up as batman and take along weapons to stop crime, and of course the individuals dressed as the villainous joker will be armed as well.
Customization will allow you to change everything from costumes to weapons while you try to hunt opponents down in Batman like environments. While 4 vs. 4 is the mode the game is showing at the moment, WBIE admits that may change before the XLBA, PSN, or PC release.
You can also check out the game site here.